1 Early pocket tag with printing on one side used 1937-50	2 Redline selvage and heavy chainstitch cuff used until 1983
3 Hidden copper rivet used on 501xx models 1937-66	4 Early WW2 era s501xx fly with generic button , still retaining crotch rivet
5 Offset belt loop as seen on 501xx models 1950-66	6 Suspender buttons on pre war s501xx,used 1922-36